package com.itheima.reggie.filter;


import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */

@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        /**
         * 1. 获取请求的uri
         * 2. 判断本次请求是否需要处理,处理指检查用户登录状态
         * 3. 若不需要处理，则直接放行
         * 4. 判断登录状态，若已登录，则直接放行
         * 5. 如果未登录，则返回未登录结果
         */

        ////1 获取请求的uri
        String requestURI = request.getRequestURI();

        log.info("拦截到请求：{}",requestURI);

        //2判断本次请求是否需要处理
        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",  //** 为通配符，表示backend下面的所有文件
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };
        //检查本次请求是否需要放行
        boolean check = check(requestURI, urls);


        //3.如果不需要处理，则直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request, response);
            return;
        }

        //4-1.判断登录状态，若已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null){
            log.info("用户已登录，用户id为{}",request.getSession().getAttribute("employee"));
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }

        //4-2.判断移动端登录状态，若已登录，则直接放行
        if (request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为{}",request.getSession().getAttribute("user"));
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            //放行
            filterChain.doFilter(request, response);
            return;
        }

        //5.如果未登录，则返回未登录结果。通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        String notlogin = JSON.toJSONString(R.error("NOTLOGIN"));
        response.getWriter().write(notlogin);
        return;


    }


    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param requestURI
     * @param urls
     * @return
     */
    public boolean check(String requestURI,String[] urls){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
